Update embassy-time (#6)

* Update embassy-time

* Update and test MSRV

* Document embassy-time requirements

Author: bugadani

.github/workflows/ci.yml

@@ -9,25 +9,29 @@ on:
     - cron: '50 4 * * *'
   workflow_dispatch:
 
-env:
-  rust_toolchain: nightly
-
 jobs:
   compile:
     name: Compile
     runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        rust_toolchain:
+          - nightly
+          - 1.83 # MSRV
+
     steps:
       - name: Setup | Checkout
         uses: actions/checkout@v2
       - name: Setup | Rust
         uses: actions-rs/toolchain@v1
         with:
-          toolchain: ${{ env.rust_toolchain }}
+          toolchain: ${{ matrix.rust_toolchain }}
           components: rustfmt, clippy
       - name: Setup | Std
-        run: rustup component add rust-src --toolchain ${{ env.rust_toolchain }}-x86_64-unknown-linux-gnu
+        run: rustup component add rust-src --toolchain ${{ matrix.rust_toolchain }}-x86_64-unknown-linux-gnu
       - name: Setup | Set default toolchain
-        run: rustup default ${{ env.rust_toolchain }}
+        run: rustup default ${{ matrix.rust_toolchain }}
       - name: Build | Fmt Check
         run: cargo fmt -- --check
       - name: Build | Clippy

Cargo.toml

@@ -1,9 +1,9 @@
 [package]
 name = "async-io-mini"
-version = "0.2.0"
+version = "0.3.0"
 authors = ["Stjepan Glavina <[email protected]>", "Ivan Markov"]
 edition = "2021"
-rust-version = "1.77"
+rust-version = "1.83"
 description = "Async I/O fork for embedded systems"
 license = "Apache-2.0 OR MIT"
 repository = "https://github.com/ivmarkov/async-io-mini"
@@ -13,7 +13,7 @@ exclude = ["/.*"]
 
 [features]
 default = ["futures-io", "futures-lite", "embassy-time"]
-embassy-time = ["embassy-time-driver", "embassy-time-queue-driver", "dep:embassy-time"]
+embassy-time = ["embassy-time-driver", "dep:embassy-time"]
 
 [dependencies]
 libc = "0.2"
@@ -22,14 +22,14 @@ heapless = "0.8"
 log = { version = "0.4", default-features = false }
 futures-io = { version = "0.3", default-features = false, optional = true, features = ["std"] }
 futures-lite = { version = "2", default-features = false, optional = true }
-embassy-time-driver = { version = "0.1", optional = true }
-embassy-time-queue-driver = { version = "0.1", optional = true }
-embassy-time = { version = "0.3", optional = true }
+embassy-time-driver = { version = "0.2", optional = true }
+embassy-time = { version = "0.4", optional = true }
 
 [dev-dependencies]
 futures-io = "0.3"
 futures-lite = "2"
-embassy-time = { version = "0.3", features = ["std", "generic-queue"] }
+embassy-time = { version = "0.4", features = ["std"] }
+embassy-time-queue-utils = { version = "0.1", features = ["generic-queue-64"] }
 async-channel = "2"
 env_logger = "0.10"
 

README.md

@@ -11,14 +11,16 @@ This crate is a fork of the splendid [`async-io`](https://github.com/smol-rs/asy
 
 ## How to use?
 
-`async-io-mini` is a drop-in, API-compatible replacement for the `Async` and `Timer` types from `async-io`.
+`async-io-mini` is an API-compatible replacement for the `Async` and `Timer` types from `async-io`.
 
 So either:
 * Just replace all `use async_io` occurances in your crate with `use async_io_mini`
 * Or - in your `Cargo.toml` - replace:
   * `async-io = "..."`
   * with `async-io = { package = "async-io-mini", ... }`
 
+Additionally, you need to provide an `embassy-time-driver` implementation. This is either done by the HAL of your MCU, or `embassy-time` provides you with a `std`-specific implementation. If you are not using `embassy-executor`, you will also need to select one of the `embassy-time/generic-queue-*` features.
+
 ## Justification
 
 While `async-io` supports a ton of operating systems - _including ESP-IDF for the Espressif MCU chips_ - it does have a non-trivial memory consumption in the hidden thread named `async-io`.  Since its hidden `Reactor` object is initialized lazily, it so happens that it is first allocated on-stack, and then it is moved into the static context. This requires the `async-io` thread (as well as _any_ thread from where you are polling sockets) to have at least 8K stack, which - by MCU standards! - is relatively large if you are memory-constrained.
@@ -39,7 +41,7 @@ Further, `async-io` has a non-trivial set of dependencies (again - for MCUs; for
 
 ## Enhancements
 
-The `Timer` type of `async_io_mini` is based on the `embassy-time` crate, and as such should offer a higher resolution on embedded operating systems like the ESP-IDF than what can be normally achieved by implementing timers using the `timeout` parameter of the `select` syscall (as `async-io` does). 
+The `Timer` type of `async_io_mini` is based on the `embassy-time` crate, and as such should offer a higher resolution on embedded operating systems like the ESP-IDF than what can be normally achieved by implementing timers using the `timeout` parameter of the `select` syscall (as `async-io` does).
 
 The reason for this is that on the ESP-IDF, the `timeout` parameter of `select` provides a resolution of 10ms (one FreeRTOS sys-tick), while
 `embassy-time` is implemented using the [ESP-IDF Timer service](https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/system/esp_timer.html), which provides resolutions up to 1 microsecond.

src/timer.rs

@@ -283,7 +283,7 @@ impl Timer {
             self.period = Duration::MAX;
 
             if let Some(waker) = self.waker.as_ref() {
-                embassy_time_queue_driver::schedule_wake(ticks, waker);
+                embassy_time_driver::schedule_wake(ticks, waker);
             }
         } else {
             self.set_never();
@@ -347,7 +347,7 @@ impl Timer {
             self.period = period;
 
             if let Some(waker) = self.waker.as_ref() {
-                embassy_time_queue_driver::schedule_wake(ticks, waker);
+                embassy_time_driver::schedule_wake(ticks, waker);
             }
         } else {
             // Overflow to never going off.
@@ -375,7 +375,7 @@ impl Timer {
                     .unwrap_or(true)
                 {
                     self.waker = Some(cx.waker().clone());
-                    embassy_time_queue_driver::schedule_wake(ticks, cx.waker());
+                    embassy_time_driver::schedule_wake(ticks, cx.waker());
                 }
             } else {
                 self.set_never();